1. Field of the Invention
The invention relates to a modular terminal, especially an isolating terminal, with a terminal housing, with a busbar formed of two sections, with two terminal elements for connecting a respective conductor to a section of the busbar and with an isolating blade which is pivotally mounted in the terminal housing, the two sections being connected to one another in a first position of the isolating blade and being separated from one another in a second position of the isolating blade, and the ends of the sections of the busbar facing away from the terminal elements being bent such that, in the first position of the isolating blade, the end of the first section of the busbar makes contact with the isolating blade on an upper contact region and the end of the second section of the busbar makes contact with the isolating blade on a lower contact region. In addition, the invention relates to a longitudinal circuit breaker with an isolating blade for pivoting arrangement in the terminal housing of a modular terminal.
2. Description of Related Art
Electrical modular terminals have been known for decades and are used in the millions in the wiring of electrical systems and devices. The terminals are generally locked onto support rails which for their part are often located in a plurality in the switching cabinet. The terminal elements in modular terminals are mainly screw-type terminals or tension spring terminals. In addition, however, insulation piercing connecting devices or leg spring terminals can also be used.
The basic type of modular terminal is the connecting terminal which has at least two terminal elements which are electrically connected to one another via an electrically conductive connecting rail, the busbar. In addition to this basic type which is often called a feed-through terminal, there is a host of different modular terminal types which are matched especially to the respective application. Examples are protective-conductor terminals, isolating blade terminals and installation terminals.
In particular, for modular terminals which are used in current transformer measurement circuits in power generation and distribution, various switching, isolating and testing tasks must often be performed. According to their use, these modular terminals are often also called measurement transformer isolating terminals. By using a longitudinal circuit breaker located in the terminal housing of the isolating terminal, the two sections of the busbar can be alternately connected to one another or separated from one another.
An electrical modular terminal in which two sections of a busbar can be separated via a gap is disclosed in German Patent Application DE 41 06 555 A1. The modular terminal described there is a two-tier terminal which has two busbars which run over one another in the terminal housing, the two busbars being separable by a gap which is accessible hum the top of the modular terminal. The gap is made as a blade gap which has an isolating blade which is pivotally mounted in a housing.
German Patent Application DE 44 44 551 A1 discloses a current transformer isolating terminal in which the gap is formed by a contact washer which is arranged to be able to pivot in the terminal housing. Making the gap as a contact washer makes it possible to alternately connect the two sections of the busbar to one another or separate them from one another. If the two sections of the busbar are separated from one another, the transformer-side section of the busbar is connected in an electrically conductive manner to a contact tip which is located additionally in the terminal housing via the contact washer, and a short circuit jumper can be plugged into this contact tip. By making the gap as a contact washer, this isolating terminal has relatively large dimensions. Moreover, the actuating angle for reliable pivoting of the contact washer out of the first position into the second position is relatively large.
The initially described isolating terminal is known from practice; in it the gap is formed by an isolating blade which is pivotally mounted in the terminal housing. The isolating blade is supported at its bottom end in a receiver in the terminal housing so that the isolating blade can be pivoted around this bearing point. While the isolating blade, in the first position makes contact with the two sections of the busbar, the isolating blade in the second position makes contact only with one of the two sections, so that the busbar is separated. To ensure a sufficiently large isolating distance between the isolating blade and the end of the second section facing away from the terminal element, a relatively large actuation angle is also necessary in this isolating terminal.
Moreover, in practice, contact separators are often used as longitudinal circuit breakers which are arranged to be able to move axially in the terminal housing and in the first position connect the two sections to one another. The longitudinal circuit breaker is fixed in its respective position using a screw.